Thank you for your help. I need to find only strings that contain Paris at the beginning and do not contain 1/5 and 5/5. I made it this way: if (/\AParis/){ if ($_ !~ /(5\/5|1\/5)/){ $line_counter++; print $_, "\n"; }; }

but how can I combine this 2 expressions? I thought that I could use negative lookahead...